Aims: Chronomodulation of immune checkpoint inhibitors (ICIs) is not well understood. The authors evaluated the circadian timing of initial ICI infusions. Patients & methods: A retrospective cohort study of patients with advanced melanoma (n = 121) was conducted. Results: Exclusive afternoon timing of the first four infusions was associated with worse overall survival (5.5 vs 24.9 months; p < 0.001) and progression-free survival (3.3 vs 7.6 months; p = 0.009) on Kaplan-Meier curves. In multivariable Cox analysis, the rate of overall survival was lower in patients who received all first four ICI infusions in the afternoon versus patients who received ≥1 of the first four infusions in the morning (hazard ratio: 2.4; p = 0.004). Conclusion: Deliberate morning scheduling for the first several ICI treatments may improve patient-centered outcomes.
Keywords: chronomodulation; circadian; immune checkpoint inhibitors; immunotherapy; melanoma.